No longer satisfied with his conscious, Treadgold is relying on electronic accountability.
"The way it's set up it involves your friends and family, which is really the way to do it. Those people, you know, they sort of don't let you backslide," said Treadgold.
Treadgold turned to online betting to help him achieve his weight lose goals.
"We've had someone lose up to 50 lbs on the site, and then we have people losing 2-3-4 lbs, so there's really no limit to StickK," said Sam Espinosa.
StickK.com offers a referee to ensure you're sticking with it. They also pay the debt with your credit card if you default or fail; along with a surprising option to donate money to a so-called anti-charity.
"That's an organization whose views you oppose, so let's say you're pro-choice, your money would go to a pro-life organization," said Espinosa.
This apparently works, as the tactic has resulted in an 80 percent success rate.
"The last thing we'd ever want to do is give you an option to send your money to an organization you actually like because then that wouldn't be much of a motivator in case you were close to not succeeding," said Espinosa.
Then there's Fatbet.net, originating as a result of two guys losing the weight war.
"We were both overweight 40 pounds, you know, we couldn't maintain like even a five-mile-per-week running program," said Adam Orkland.
Now at fighting weight, and running far more than they ever had previously, they offer their program free of charge to encourage others. They don't handle financial transactions, yet offer accountability by logging weight daily to get encouraged or razzed by friends and family.
University studies involving dieting or smoking cessation where financial incentives were used, found losing or gaining money was a definite motivator. But some experts say the results might be temporary.
"I think it works mostly though for more 'A' type personalities who love the challenge and don't like to lose," said psychologist Leslie Seppinni. "I also think, on the opposite end, it doesn't promote long term weight lose maintenance, so what do you do once the betting's done?"
So far Jonathan has kept his swimming goal, but isn't an Olympic hopeful just yet.
"I don't know if I'm quite ready to challenge the Phelps's of the world, but I'm getting there," said Treadgold.